The present invention relates to cosmetics containing an oily bidiglyceryl ether compound, and has for its object to provide novel cosmetics which are free from any stimulating action of surface active agents exercised on the skin, are virtually stable with respect to hydrolysis and can endow the skin with proper wettability and softening action.
Oily solvents used in cosmetics are generally selected from fats and oils (triglyceride), waxes, higher alcohols, higher fatty acids, hydrocarbons, esters and the like. Most of the oily solvents that have been heretofore known are not easily dissolved in water-alcohol based cosmetics having an alcohol content of less then 50%, i.e., lotions such as toilet lotions, cosmetic removers, hair tonics, cleansers and body lotions. While castor oil, isopropyl myristate (hereinafter referred to as I.P.M.), oleyl alcohol, hexadecyl alcohol etc. are exceptionally employed in such lotions, they can be added thereto only in small amounts due to their poor solubility with the result that no proper wettability is given to the skin. Furthermore, when it is desired to add fats and oils to the cosmetics having a smaller alcohol content such as cosmetic removers, they need to be solubilized with the aid of a specific surface active agent having a relatively high HLB (the average HLB nearly equals 15). However, the use of such a surface active agent is responsible for a variety of dermatitis recently caused by cosmetics and consequently disadvantageous. A compound of a dibasic ester type such as polypropylene glycol malate is also known. However, such a compound tends to undergo hydrolysis with time in a water-alcohol system, resulting in a change in quality and hence unsatisfactory stability.
As a consequence of extensive investigations performed from the foregoing viewpoint, we have found a novel compound which is easily dissolved in water-alcohol based cosmetics, is well compatible with other oily solvents and is extremely stable in a water-alcohol system without suffering substantial hydrolysis.